The present invention pertains to a method and apparatus for allowing a subscriber to access information from several information providers, usually for a fee. More particularly, the present invention pertains to a method and apparatus for allowing a subscriber to obtain access to individual programs where the subscriber is only charged for the programs which have been accessed. The present invention also pertains to a method and apparatus for allowing a subscriber to obtain access to a package of programs in a uni-directional communication with the program service provider.
Some types of information broadcast systems are commonly known. One type is an over the air broadcast by use of UHF and VHF signals which can be freely obtained by anyone who can pick up such signals with an appropriate antenna. These systems generate revenue by selling airtime for commercial broadcasts. A second type of system is subscription system where a subscriber subscribes to the broadcast system which is provided, for example, through a cable line or a satellite dish.
The subscription systems protect the content of the information in the broadcast from being read by non subscribing cable or satellite dish users by complex encryption schemes. Such schemes often use a new encryption method for every discrete period of time within the broadcast, i.e. every 3 seconds. These schemes also commonly require the subscriber to have a conditional access module (CAM) which receives and decrypts the encrypted content data. In order for the CAM to decrypt the information, ECMs (Entitlement Control Messages) are interleaved with data packets containing the content information which instruct the CAM how to decrypt the content information. However, in typical subscription broadcast systems, the subscriber is only able to subscribe to one information provider, i.e. they are single subscription systems. Generally, the CAM of one information provider will not be able to interpret the ECMs of another information provider. This limits the subscriber""s ability to freely choose programs since the subscriber is only able to receive the programs offered by one particular information provider.
One solution is for the subscriber to subscribe to several different information providers. This would require the subscriber to have a CAM for each provider and to be charged separately by each provider. Additionally, a subscriber may have access to several information providers in his/her geographic region, such as, several local broadcast service providers and cable service providers. Clearly, this is an expensive and highly undesirable choice.
Another solution is known as SIMULCRYPT, in which the ECMs of a plurality of information providers are interleaved throughout the content of the broadcast. This allows different service providers to use the same content information, thus sharing their resources. However, SIMULCRYPT does not provide the subscribers any more flexibility since the CAM of the subscriber can only interpret one of the ECMs, i.e. only the ECM of their information provider. Another problem of SIMULCRYPT is that it involves a high degree of cooperation between competing broadcasters, such as requiring competing broadcasters to provide confidential ECM information to be broadcast on the broadcast mechanisms.
Furthermore, the advent of HDTV (high definition TV) will likely enable traditional air broadcast information providers to provide subscription air broadcasts, since digital data in the broadcast could easily be encrypted using known techniques. A single broadcaster is expected to be able to allocate their HDTV broadcast channel (provided to the broadcasters by the Federal Communications Commission (FCC)) into as many as four, or more, air broadcast channels. Additionally, many of those channels may be encrypted for subscription channels, i.e. up to three of the HDTV channels. Since there are often at least four television networks which broadcast in single geographic area, the number of subscription information providers available to a single subscriber will greatly increase if each of the networks provides a plurality of subscription channels. This is even a greater problem for a subscriber who lives on a border between two geographic broadcast areas, such as between Baltimore and Washington D.C., and thus would potentially have to deal with twice as many subscription channels from twice as many information providers. It would be very inconvenient for a subscriber to subscribe to each of these subscription channels since the subscriber would need to have several different CAMs to decrypt the several different channels, and the subscriber would have to pay each of the several. different information providers.
One possible solution is for the networks to closely cooperate with each other, trading ECMs and encryption equipment. Thus, the CAM provided by one network, for example ABC, would be able to decrypt the content information provided by other networks, and ABC could collect the subscription fee from the subscriber and redistribute the appropriate amounts to the other networks. However, such a solution appears to require a very high degree of cooperation and trust, neither of which are likely to exist in the competitive broadcast industry. For example, if the security of another network, such as NBC, was compromised, ABC would have little incentive to repair any ABC CAMs to correct the security breach affecting NBC. Additionally, the degree of cooperation would multiply to provide subscribers on a border of adjacent broadcast areas with the same service.
A proposed solution for obtaining access to encrypted broadcast data is disclosed in U.S. Pat. No. 5,010,571 to Katznelson. Katznelson disclose a process for obtaining access to encrypted information stored on a disc by using an authorization and key distribution terminal (service provider) to send the decryption keys to the customer, after the customer has requested such keys in a customer initiated communication. However, in this proposed solution, the customer must contact the service provider prior to accessing any discs (information), thus offline operations and/or a unidirectional operations are not possible. Additionally, it may be a great inconvenience to the customer to request access every time it is desired, since such request would take additional time and effort by the customer, both of which may be significant depending on the speed and availability of connection to the service provider.
Another approach to obtaining access to encrypted broadcasted information is proposed in U.S. Pat. No. 5,703,951 to Dolphin. Dolphin discloses a procedure wherein a disc (CD-ROM) containing a plurality of encrypted magazines is distributed to customers, who are able to access the individual magazines to which they have a corresponding key stored on a PCMCIA card. If the customer does not have the corresponding key on their PCMCIA card, then they can contact a service provider for such key. However, this proposal is per publisher based; that is, there is no procedure for providing the customer access to magazines published by several different publishers. In fact, the only way that the user could get magazines from other publishers is to have competing publishers share confidential encryption information, and share billing receipts with each other. This is an undesirable business procedure, since a publisher will not be able to truly compete with its competitors. Another related drawback of this proposal is that the customer has very limited flexibility in choosing which magazines to access, since the customer is limited to the particular magazines which happen to be stored on the CD-ROM distributed by the publisher.
It is an object of the invention to provide subscribers with a cost effective method for providing a plurality of subscription services in a geographic area.
It is another object of the invention to provide subscribers at the borders of adjacent broadcast areas with a cost effective method of obtaining plurality of subscription services.
It is yet another object of the invention to allow a user to choose to receive a package of content from a service provider, or to receive individual programs of content from the service provider.
It is yet another object of the invention to allow a subscriber to receive content data through an off-line operation.
It is yet another object of the invention to allow a subscriber to receive content data through a unidirectional communication with a service provider.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, the method of this invention may comprise a method of distributing content data from a content provider device to a subscriber, the content provider including an encryption device, the subscriber having a set top box including a decryption device, the method comprising the steps of: encrypting content using the encryption device; distributing the encrypted content with content identifiers from the content provider to the subscriber; distributing keys for decrypting the encrypted content from the content provider to a service provider; distributing the keys from the service provider to the subscriber; and accessing the content by decrypting the content using the decryption device.
In a further aspect of the present invention, in accordance with its objects and purposes, the method hereof may also preferably comprise the steps of: logging access of the content by the subscriber in a log contained on a non-volatile memory; and sending the log to the service provider.
In yet a further aspect of the present invention, in accordance with its objects and purposes, the method hereof may further preferably include distributing rules with the keys, wherein the steps of accessing the content and logging access of the content are performed according to the rules.
In yet a further aspect of the present invention, the step of distributing the keys may further preferably include distributing the keys by broadcasting the keys to the subscriber.
In yet a further aspect of the present invention, the step of distributing the encrypted content may further preferably be performed by multiple content providers, and the step of distributing keys is performed by multiple service providers, and wherein the subscriber interacts with at least one of said multiple content providers and at least one of said multiple service providers.
In yet a further aspect of the present invention, the step of distributing the keys may further preferably include distributing encrypted content from a single content provider to a plurality of broadcasters; and broadcasting the encrypted content to the subscriber.
In yet a further aspect of the present invention, wherein the set top box may further preferably include a display device and a menu navigation device, and may further preferably comprise the steps of: displaying a menu on said display device; receiving input from said menu navigation device; and controlling access to content based on the received input.
Another method according to the present invention may comprise a method of distributing content data from a content provider to a subscriber, the subscriber having a set top box including a decryption device, the method comprising the steps of: encrypting the content data using a content key and an index, in a series of indices, corresponding to a content packet, in a series of content packets; forming a data stream by interleaving the series of indices with a series of content packets; transmitting the data stream to the set top box; and decrypting the content packet using a content key and the index corresponding to the content packet in a series of indices.
In a further aspect of the present invention, in accordance with its objects and purposes, the other method hereof may also preferably comprise encrypting and decrypting by hashing the indices with the content key.
An apparatus according to the present invention may comprise an apparatus for receiving and decrypting encrypted content data from a content provider to a subscriber via a broadcaster, using a content descriptor provided by a service provider, the apparatus comprising: a receiver for receiving the encrypted content; a decryptor for decrypting the encrypted content using the content descriptor; and a controller for controlling the decryptor and for communicating with the service provider, thereby providing the subscriber access to the content data.
In a further aspect of the present invention, in accordance with its objects and purposes, the apparatus hereof may also preferably comprise, a logging device for logging access to the content data, wherein the controller controls the logging device log access to the content data according to rules contained in the content descriptor.
In yet a further aspect of the present invention, in accordance with its objects and purposes, the apparatus hereof may also preferably comprise communication control logic, the communication control logic being responsive to the controller to communicate with the service provider.
In a further aspect of the present invention, in accordance with its objects and purposes, the apparatus hereof may also preferably comprise a menu generator for generating a menu, having a plurality of operations, to be displayed on a display device; and a menu navigator for providing a user selection of said operations to said controller.
The invention is advantageous over the SIMULCRYPT because it provides the conditional access control to a subscriber through a different channel than the content, thus broadcaster can maximize its business by disseminating the broadcast to as many people as possible without investing resources to protect the content of the broadcast. Furthermore, the broadcaster is no longer required to allocate space on the broadcast transmission for transmitting conditional access control data such as keys to decrypt the content data. Additionally, unlike SIMULCRYPT, the present invention does not require significant cooperation between competing broadcasters or competing content providers, and thus does not require them to share confidential conditional access information or subscription fees.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.